Bullet or projectile for firearms.



Patented J un@ i, 191.5,

A` DOSHEGEANSKY.

BULLET DR PROJECTILE FOR FIREARMS.

APPLICATION m50 Nov.29. 19:3.

ALEXANDER DOBREGEANSKY, F ST. PETERSBURG, RUSSIA.

BULLET OB PROJECTILE FOR FIREABMS.

Specleation of Letters Patent.

rasanten June a, reis..

Application filed November 29, 1913. Serial No. 803,691.

To all wkomtt may concern Be it known that I, ALEXANDER Dolma- GEANsKY, subject of the Emperor of Russia, and resident of St. Petersburg, Russia,

colonel of the Guards-Infanterie of Russian Army, have invented new and useful Improvements in Bullets or Projectiles for Firearms, of which the following is a specification.

My invention has for its object the increasing of the accuracy of aim and the projectiles initial velocity, without increasing `the maximum permissible pressure of powder gases in the barrel of hand iire arms. Besides this, the construction of the bullet permits it, to maintain, to a great extent, the speed when fiying, by which the utmost piercing capacity of the bullet is conditioned. All their ballistic qualities are attained because of the fact, that the center of gravity of the bullet is transferred nearer toits head portion and the core of the bullet is made ont of two metals: a heavy and soft metal (lead, for instance), and light and hard metal (duraluminium, for instance). Both parts of the core are connected by means of a general hard covering, the core and the covering being contracted at the eX- tremity.

In the drawings z-Figure 1 is a longitudinal section of a bullet constructed in accordance with the invention, and designed for Russian 3-line rifles of the'1891 model, Fig. 2 is a front View of another embodiment of the invention designed for guns, rnd Fig. 3 is a section on the line L -b of In the lead core l is made a long central cavity, into which the cone 2 made of durallllmnium is inserted. The height of this cone 2 is calculated in such a manner, that the air chamber 3 should remain between it and the lead core.

The core is covered, as usual, by a nickel coverin 4, which, bending over at the back, firmly :stens both arts of the core. The

rear end of the bul et, as is seen from the drawing, is somewhat contracted. Owing to such a construction, the center of gravity of the bullet is in theY front half of 1t, near the head portion, by which means its stability when ilying is conditioned.

On iriirgthe cone 2 is pushed by the pressure orf` the powder ases to the front (as is shown in dotted ines) in the lead core, the rear part of the latterand the portion of the coverin expanding to the si es,

the cone 2 meets a resistance of air con' tained 1n the chamber 3, Wh1ch, formin an air cushion, prevents the cone 2being pu ed farther than a certain limit. Owing to this fact, theexcessive opening of the portion l and the covering 4 is avoided, as well as the superfluous pressing of these parts to the rilings, as is the case withordinary bnllets, in which the powder gases expand the rear end of the core and the covering of the bullet directly.

Owing to such a construction, on tiring with the proposed bullet, smaller maximum pressures are obtained than when firing with the ordinary bullet. The contracting of the rear end of rthe bullet aids the free flow of the air and decreases the vacuum space behind the bullet and therefore hel s 4, which adjoins lity]V tightly pressing '5 to attain a smaller resistance of air in t e Hight of the bullet and consequently preserves its speed.

fTests eilected with firing the proposed bullet from a 3-line rifle Tula Cartridge Works in that the initial speed with a standard charge attained on an average up to 883 meters per second, with a maximum pressure of 2580 atmos. At the same time, owing to the sta-- bility of the bullet when flying, the declination from the average velocity did not exceed 17 meters per second. y Suchresults give reason to en ect, that, by somewhat increasing the weig t of the charge, an initial velocity up to 900 ine/tersl per second may be obtained when firing with the proposed bnL let, at a maximum pressure, not exceeding the limit of 3200 atm. establlshed for 3-line rifles.

It is obvious, that the method of transferring the center of gravity nearer to the head portion, used in the construction of the proposed bullet, may also be made use of 'for gun projectiles maintaining the same ballistical qualities, which are conditioned at the Imperia?N Tula,haveproved,"

by the arran ement of the center of ,f fravity at the hea portion of the bullet. When constructing such projectiles, the chamber 3 becomes superinous, as in the projectile I and to ll it with a light metal (alnrninium,

for instance).

What I claim is:

A projectile for fire arms, composed bf a core ofsoft heavy metal having a, central longitudinally extending substantially -con1' cal chamber opening at the base, and a cone of light hard metal inserted in the chamber, the height of the cone being less than the depth of the chamber to form an air chamber at the inner end of the chamber and between the cone and the core, and a covering for the core, said covering having ari-inward extension at the base of the core and engaging the base of Athe cone to 

